In this paper, we extend Porteus (1986) to generalize the economic production quantity (EPQ) model with finite production rate and to derive an exact expression for the expected total annual cost function when maintenance actions and capital investment in setup cost reduction are adopted. In addition, the uniqueness property of the optimal lot size and the bounds of optimal lot size are derived...

We investigate the dynamic lot-size problem under stochastic and non-stationary demand over the planning horizon. The problem is tackled by using three popular heuristic methods from the fields of evolutionary computation and swarm intelligence, namely particle swarm optimization, differential evolution and harmony search. To the best of the authors’ knowledge, this is the first investigation o...

BACKGROUND AND OBJECTIVES There are several formulations of propofol available to the anesthesiologist for clinical use. The aim of this study was to analyze the physicochemical properties, pharmacodynamic effect, and pharmaceutical and clinical equivalence of the reference drug propofol as well as a similar formulation. METHOD Sixteen volunteers were enrolled in this randomized, double-blind...

UNLABELLED BACKGROUND Estimation of vaccination coverage at the local level is essential to identify communities that may require additional support. Cluster surveys can be used in resource-poor settings, when population figures are inaccurate. To be feasible, cluster samples need to be small, without losing robustness of results. The clustered LQAS (CLQAS) approach has been proposed as an a...

This paper considers a dynamic lot size problem faced by a producer who supplies a single product to multiple customers. Characterized by their backorder costs as well as shipping costs, the customer with a high backorder cost is the one whose need for the product is more critical than the need of a customer with a low backorder cost. We show that the general problem with time-varying, customer...

One of the fundamental problems in operations management is to determine the optimal investment in capacity. Capacity investment consumes resources and the decision is often irreversible. Moreover, the available capacity level affects the action space for production and inventory planning decisions directly. In this paper, we address the joint capacitated lot sizing and capacity acquisition pro...

Lot quality assurance sampling (LQAS) surveys are commonly used for monitoring and evaluation in resource-limited settings. Recently several methods have been proposed to combine LQAS with cluster sampling for more timely and cost-effective data collection. For some of these methods, the standard binomial model can be used for constructing decision rules as the clustering can be ignored. For ot...

BACKGROUND High quality program data is critical for managing, monitoring, and evaluating national HIV treatment programs. By 2009, the Malawi Ministry of Health had initiated more than 270,000 patients on HIV treatment at 377 sites. Quarterly supervision of these antiretroviral therapy (ART) sites ensures high quality care, but the time currently dedicated to exhaustive record review and data ...